Ammonia PP / M62
EN Method Reference Book 1.0
13
EN
Analyses
The following table identifies the output values can be converted into other citation
forms.
Unit
Cite form
Scale Factor
mg/l
N
1
mg/l
NH
4
1.288
mg/l
NH
3
1.22
Chemical Method
Salicylate
Appendix
Interferences
Persistant Interferences
• Sulphide intensifies the colouration.
Removeable Interferences
• Iron interferes with the test at all concentrations. Iron interference is eliminated as
follows.
a) Determine the concentration of iron present in the sample by performing a total
Iron test.
b) in the blank, use the same iron concentration as that determined instead of the
deionised water.
• Less common interferences such as Hydrazine and Glycine will cause intensified
colours in the prepared sample. Turbidity and colour will give erroneous high values.
For samples where there are severe interferences, distillation will be necessary.
Interference
from / [mg/l]
Ca
2+
1000 (CaCO
3
)
Mg
2+
6000 (CaCO
3
)
NO
3
-
100
NO
2
-
12
PO
4
3-
100
SO
4
2-
300
